You do not need to type a key during installation. The Windows installer should automatically detect the key in the BIOS and activate itself. If the installer asks for a key and you want to skip it, look for a button that says "I don't have a product key" or similar text. Once connected to the internet, it should auto-activate.
Windows Embedded 8.1 Industry Pro is a specialized version of the Windows 8.1 operating system designed for edge devices in industries like retail, manufacturing, and healthcare windows 81 embedded industry pro product key
For offline activation (air-gapped industrial devices), you would use slmgr /dli to get the Installation ID, then call Microsoft’s automated phone system. You do not need to type a key during installation